This is too fascinating

To make a long story short, McPhee describes two things: how Switzerland requires military service from every able-bodied male Swiss citizen—a model later emulated and expanded by Israel—and how the Swiss military has, in effect, wired the entire country to blow in the event of foreign invasion. To keep enemy armies out, bridges will be dynamited and, whenever possible, deliberately collapsed onto other roads and bridges below; hills have been weaponized to be activated as valley-sweeping artificial landslides; mountain tunnels will be sealed from within to act as nuclear-proof air raid shelters; and much more.